javax.jms.QueueRequestor Maven / Gradle / Ivy
/*
* @(#)QueueRequestor.java 1.21 02/04/09
*
* Copyright 1997-2002 Sun Microsystems, Inc. All Rights Reserved.
*
* SUN PROPRIETARY/CONFIDENTIAL.
* This software is the proprietary information of Sun Microsystems, Inc.
* Use is subject to license terms.
*
*/
package javax.jms;
/** The QueueRequestor helper class simplifies
* making service requests.
*
* The QueueRequestor constructor is given a non-transacted
* QueueSession and a destination Queue. It creates a
* TemporaryQueue for the responses and provides a
* request method that sends the request message and waits
* for its reply.
*
*
This is a basic request/reply abstraction that should be sufficient
* for most uses. JMS providers and clients are free to create more
* sophisticated versions.
*
* @version 1.0 - 8 July 1998
* @author Mark Hapner
* @author Rich Burridge
*
* @see javax.jms.TopicRequestor
*/
public class QueueRequestor {
QueueSession session; // The queue session the queue belongs to.
Queue queue; // The queue to perform the request/reply on.
TemporaryQueue tempQueue;
QueueSender sender;
QueueReceiver receiver;
/** Constructor for the QueueRequestor class.
*
*
This implementation assumes the session parameter to be non-transacted,
* with a delivery mode of either AUTO_ACKNOWLEDGE or
* DUPS_OK_ACKNOWLEDGE.
*
* @param session the QueueSession the queue belongs to
* @param queue the queue to perform the request/reply call on
*
* @exception JMSException if the JMS provider fails to create the
* QueueRequestor due to some internal
* error.
* @exception InvalidDestinationException if an invalid queue is specified.
*/
public
QueueRequestor(QueueSession session, Queue queue) throws JMSException {
this.session = session;
this.queue = queue;
tempQueue = session.createTemporaryQueue();
sender = session.createSender(queue);
receiver = session.createReceiver(tempQueue);
}
/** Sends a request and waits for a reply. The temporary queue is used for
* the JMSReplyTo destination, and only one reply per request
* is expected.
*
* @param message the message to send
*
* @return the reply message
*
* @exception JMSException if the JMS provider fails to complete the
* request due to some internal error.
*/
public Message
request(Message message) throws JMSException {
message.setJMSReplyTo(tempQueue);
sender.send(message);
return (receiver.receive());
}
/** Closes the QueueRequestor and its session.
*
*
Since a provider may allocate some resources on behalf of a
* QueueRequestor outside the Java virtual machine, clients
* should close them when they
* are not needed. Relying on garbage collection to eventually reclaim
* these resources may not be timely enough.
*
*
Note that this method closes the QueueSession object
* passed to the QueueRequestor constructor.
*
* @exception JMSException if the JMS provider fails to close the
* QueueRequestor due to some internal
* error.
*/
public void
close() throws JMSException {
// publisher and consumer created by constructor are implicitly closed.
session.close();
tempQueue.delete();
}
}